U.S. patent application number 14/165645 was filed with the patent office on 2015-07-30 for semiconductor device including flexible leads.
This patent application is currently assigned to Infineon Technologies AG. The applicant listed for this patent is Infineon Technologies AG. Invention is credited to Theng Chao Long, Tian San Tan.
Application Number | 20150214179 14/165645 |
Document ID | / |
Family ID | 53523093 |
Filed Date | 2015-07-30 |
United States Patent
Application |
20150214179 |
Kind Code |
A1 |
Tan; Tian San ; et
al. |
July 30, 2015 |
SEMICONDUCTOR DEVICE INCLUDING FLEXIBLE LEADS
Abstract
A semiconductor device includes a semiconductor chip including a
transistor. A first flexible lead is electrically coupled to a
first electrode on a first surface of the semiconductor chip. A
second flexible lead is electrically coupled to a second electrode
on the first surface of the semiconductor chip. A third flexible
lead is electrically coupled to a third electrode on a second
surface of the semiconductor chip, the second surface opposite to
the first surface.
Inventors: |
Tan; Tian San; (Melaka,
MY) ; Long; Theng Chao; (Melaka, MY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Infineon Technologies AG |
Neubiberg |
|
DE |
|
|
Assignee: |
Infineon Technologies AG
Neubiberg
DE
|
Family ID: |
53523093 |
Appl. No.: |
14/165645 |
Filed: |
January 28, 2014 |
Current U.S.
Class: |
257/139 ;
257/288; 257/773; 438/126 |
Current CPC
Class: |
H01L 23/564 20130101;
H01L 2224/29294 20130101; H01L 2224/29347 20130101; H01L 2224/83411
20130101; H01L 2224/8384 20130101; H01L 2224/32014 20130101; H01L
2924/15747 20130101; H01L 24/89 20130101; H01L 2224/83447 20130101;
H01L 24/32 20130101; H01L 2224/29147 20130101; H01L 2224/83411
20130101; H01L 2224/83413 20130101; H01L 2224/83444 20130101; H01L
2224/83411 20130101; H01L 2224/83825 20130101; H01L 2224/8384
20130101; H01L 2924/181 20130101; H01L 23/49537 20130101; H01L
2224/33181 20130101; H01L 21/565 20130101; H01L 24/33 20130101;
H01L 2224/29344 20130101; H01L 2224/29294 20130101; H01L 2224/83447
20130101; H01L 24/64 20130101; H01L 2224/83413 20130101; H01L
2224/29339 20130101; H01L 24/70 20130101; H01L 2224/83444 20130101;
H01L 2224/83416 20130101; H01L 2224/291 20130101; H01L 2924/15701
20130101; H01L 2924/181 20130101; H01L 2224/29111 20130101; H01L
2224/83444 20130101; H01L 2224/83416 20130101; H01L 2224/83411
20130101; H01L 23/49555 20130101; H01L 2224/83411 20130101; H01L
2224/83801 20130101; H01L 2924/15747 20130101; H01L 2224/29111
20130101; H01L 2224/32503 20130101; H01L 2924/15165 20130101; H01L
23/3107 20130101; H01L 2224/32225 20130101; H01L 2924/15701
20130101; H01L 2224/83444 20130101; H01L 2224/83825 20130101; H01L
2924/13091 20130101; H01L 24/29 20130101; H01L 2924/13055 20130101;
H01L 2224/29111 20130101; H01L 2224/29347 20130101; H01L 2224/83411
20130101; H01L 2924/00014 20130101; H01L 2924/01082 20130101; H01L
2924/00014 20130101; H01L 2924/00014 20130101; H01L 24/83 20130101;
H01L 2224/29339 20130101; H01L 2224/83411 20130101; H01L 2224/29147
20130101; H01L 2224/291 20130101; H01L 2224/29111 20130101; H01L
2224/29344 20130101; H01L 2224/83801 20130101; H01L 2924/00014
20130101; H01L 2924/0105 20130101; H01L 2924/00014 20130101; H01L
2924/01014 20130101; H01L 2924/01047 20130101; H01L 2924/00014
20130101; H01L 2924/01029 20130101; H01L 2924/014 20130101; H01L
2924/01028 20130101; H01L 2924/014 20130101; H01L 2924/01047
20130101; H01L 2924/00 20130101; H01L 2924/01029 20130101; H01L
2924/01032 20130101; H01L 2924/00014 20130101; H01L 2924/01029
20130101; H01L 2924/01082 20130101; H01L 2924/01047 20130101; H01L
2924/0105 20130101; H01L 2924/01051 20130101; H01L 2924/00014
20130101; H01L 2924/01047 20130101; H01L 2924/01029 20130101; H01L
2924/01029 20130101; H01L 2924/01049 20130101; H01L 2924/00014
20130101; H01L 2924/01047 20130101; H01L 2924/0105 20130101 |
International
Class: |
H01L 23/00 20060101
H01L023/00; H01L 23/31 20060101 H01L023/31; H01L 21/56 20060101
H01L021/56 |
Claims
1. A semiconductor device comprising: a semiconductor chip
comprising a transistor; a first flexible lead electrically coupled
to a first electrode on a first surface of the semiconductor chip,
a portion of the first flexible lead aligned with the first
electrode in a direction perpendicular to the semiconductor chip; a
second flexible lead electrically coupled to a second electrode on
the first surface of the semiconductor chip, a portion of the
second flexible lead aligned with the second electrode in the
direction perpendicular to the semiconductor chip; and a third
flexible lead electrically coupled to a third electrode on a second
surface of the semiconductor chip, the second surface opposite to
the first surface, a portion of the third flexible lead aligned
with the third electrode in the direction perpendicular to the
semiconductor chip.
2. The semiconductor device of claim 1, wherein each of the first
flexible lead, the second flexible lead, and the third flexible
lead comprises a pre-formed ribbon lead having a spring-like
characteristic.
3. The semiconductor device of claim 1, wherein each of the first
flexible lead, the second flexible lead, and the third flexible
lead comprises an elastic or softening material.
4. The semiconductor device of claim 1, wherein each of the first
flexible lead, the second flexible lead, and the third flexible
lead comprises a solder material.
5. The semiconductor device of claim 1, wherein the transistor is a
metal-oxide-semiconductor field-effect transistor, wherein the
first electrode comprises a gate electrode of the transistor,
wherein the second electrode comprises a source electrode of the
transistor, and wherein the third electrode comprises a drain
electrode of the transistor.
6. The semiconductor device of claim 5, wherein the first flexible
lead has a first width, wherein the second flexible lead has a
second width greater than the first width, and wherein the third
flexible lead has a third width greater than the first width.
7. The semiconductor device of claim 1, wherein the transistor is
an insulated gate bipolar transistor, wherein the first electrode
comprises a base electrode of the transistor, wherein the second
electrode comprises a collector electrode of the transistor, and
wherein the third electrode comprises an emitter electrode of the
transistor.
8. The semiconductor device of claim 7, wherein the first flexible
lead has a first width, wherein the second flexible lead has a
second width greater than the first width, and wherein the third
flexible lead has a third width greater than the first width.
9. A semiconductor device comprising: a semiconductor chip
comprising a transistor, the semiconductor chip having a first
surface and a second surface opposite to the first surface; a first
flexible lead electrically coupled to the first surface, a portion
of the first flexible lead aligned with the semiconductor chip in a
direction perpendicular to the semiconductor chip; a second
flexible lead electrically coupled to the second surface, a portion
of the second flexible lead aligned with the semiconductor chip in
the direction perpendicular to the semiconductor chip; and a mold
compound encapsulating the semiconductor chip.
10. The semiconductor device of claim 9, wherein the mold compound
comprises a soft or elastic mold compound.
11. The semiconductor device of claim 9, wherein the mold compound
encapsulates a portion of the first flexible lead.
12. The semiconductor device of claim 11, wherein the mold compound
encapsulates a portion of the second flexible lead.
13. The semiconductor device of claim 11, wherein the mold compound
encapsulates the semiconductor chip and the portion of the first
flexible lead such that the second flexible lead is exposed.
14. The semiconductor device of claim 9, wherein the mold compound
comprises a spacer on a portion of the first flexible lead such
that with the semiconductor device mounted on a printed circuit
board, the spacer defines an air gap between the printed circuit
board and the first flexible lead.
15. The semiconductor device of claim 9, further comprising: a
ferrite coil around the first flexible lead.
16. A method for fabricating a semiconductor device, the method
comprising: electrically coupling a first electrode on a first
surface of a semiconductor chip to a first flexible lead such that
a portion of the first flexible lead is aligned with the first
electrode in a direction perpendicular to the semiconductor chip,
the semiconductor chip comprising a transistor; electrically
coupling a second flexible lead to a second electrode on a second
surface of the semiconductor chip such that a portion of the second
flexible lead is aligned with the second electrode in the direction
perpendicular to the semiconductor chip, the second surface
opposite to the first surface; and electrically coupling a third
flexible lead to a third electrode on the second surface of the
semiconductor chip such that a portion of the third flexible lead
is aligned with the third electrode in the direction perpendicular
to the semiconductor chip.
17. The method of claim 16, further comprising: encapsulating the
semiconductor chip and at least a portion of the first flexible
lead, the second flexible lead, and the third flexible lead with a
mold compound.
18. The method of claim 17, wherein the mold compound comprises a
soft or elastic mold compound.
19. The method of claim 16, further comprising: electrically
coupling the first flexible lead, the second flexible lead, and the
third flexible lead to a flexible printed circuit board.
20. The method of claim 19, further comprising: flexing the printed
circuit board such that the printed circuit board is curved.
Description
BACKGROUND
[0001] Power semiconductor devices, such as transistors, are used
in a wide variety of applications, such as portable electronic
devices (e.g., mobile phones). Power transistors include Insulated
Gate Bipolar Transistor (IGBT) semiconductor chips and
Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET)
semiconductor chips. The semiconductor chips have varying voltage
and current ratings. The semiconductor chips are made from Si, SiC,
GaN, GaAs, or other suitable substrates. Electronic devices
continue to take on new shapes and sizes that make conventional
power semiconductor devices difficult to integrate into the
electronic devices.
[0002] For these and other reasons, there is a need for the present
invention.
SUMMARY
[0003] One embodiment provides a semiconductor device. The
semiconductor device includes a semiconductor chip including a
transistor. A first flexible lead is electrically coupled to a
first electrode on a first surface of the semiconductor chip. A
second flexible lead is electrically coupled to a second electrode
on the first surface of the semiconductor chip. A third flexible
lead is electrically coupled to a third electrode on a second
surface of the semiconductor chip, the second surface opposite to
the first surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The accompanying drawings are included to provide a further
understanding of embodiments and are incorporated in and constitute
a part of this specification. The drawings illustrate embodiments
and together with the description serve to explain principles of
embodiments. Other embodiments and many of the intended advantages
of embodiments will be readily appreciated as they become better
understood by reference to the following detailed description. The
elements of the drawings are not necessarily to scale relative to
each other. Like reference numerals designate corresponding similar
parts.
[0005] FIGS. 1A-1B illustrate one embodiment of a semiconductor
device.
[0006] FIG. 2 illustrates a side view of one embodiment of a
semiconductor device.
[0007] FIG. 3 illustrates a side view of another embodiment of a
semiconductor device.
[0008] FIG. 4 illustrates a side view of another embodiment of a
semiconductor device.
[0009] FIGS. 5A-5C illustrate embodiments of a flexible lead.
[0010] FIGS. 6A-6B illustrate embodiments of a semiconductor device
coupled to a Printed Circuit Board (PCB).
[0011] FIGS. 7A-7B illustrate embodiments of a semiconductor device
coupled to a flexible PCB.
[0012] FIGS. 8A-8E illustrate one embodiment of a method for
fabricating a semiconductor device.
[0013] FIGS. 9A-9C illustrate one embodiment of a mold compound
arrangement for a semiconductor device.
[0014] FIGS. 10A-10C illustrate another embodiment of a mold
compound arrangement for a semiconductor device.
[0015] FIGS. 11A-11C illustrate another embodiment of a mold
compound arrangement for a semiconductor device.
[0016] FIGS. 12A-12C illustrate another embodiment of a mold
compound arrangement for a semiconductor device.
[0017] FIGS. 13A-13C illustrate another embodiment of a mold
compound arrangement for a semiconductor device.
[0018] FIGS. 14A-14D illustrate embodiments of flexible lead
arrangements for a semiconductor device.
[0019] FIG. 15 illustrates a side view of one embodiment of a
semiconductor device including ferrite coils around the flexible
leads.
[0020] FIGS. 16A-16B illustrate embodiments of flexible lead
arrangements for a semiconductor device including a source sense
flexible lead.
DETAILED DESCRIPTION
[0021] In the following Detailed Description, reference is made to
the accompanying drawings, which form a part hereof, and in which
is shown by way of illustration specific embodiments in which the
disclosure may be practiced. In this regard, directional
terminology, such as "top," "bottom," "front," "back," "leading,"
"trailing," etc., is used with reference to the orientation of the
Figure(s) being described. Because components of embodiments can be
positioned in a number of different orientations, the directional
terminology is used for purposes of illustration and is in no way
limiting. It is to be understood that other embodiments may be
utilized and structural or logical changes may be made without
departing from the scope of the present disclosure. The following
detailed description, therefore, is not to be taken in a limiting
sense, and the scope of the present disclosure is defined by the
appended claims.
[0022] It is to be understood that the features of the various
exemplary embodiments described herein may be combined with each
other, unless specifically noted otherwise.
[0023] As used herein, the term "electrically coupled" is not meant
to mean that the elements must be directly coupled together and
intervening elements may be provided between the "electrically
coupled" elements.
[0024] FIG. 1A illustrates a cross-sectional view and FIG. 1B
illustrates a top view of one embodiment of a semiconductor device
100. Semiconductor device 100 includes a semiconductor chip 102,
flexible leads 112, 114, and 116, and a mold compound 118. A first
electrode on a first surface 104 of semiconductor chip 102 is
electrically coupled to a first flexible lead 112 through a first
solder or sintered joint 108. A second electrode on a second
surface 106 opposite to the first surface 104 of semiconductor chip
102 is electrically coupled to a second flexible lead 114 through a
second solder or sintered joint 110. A third electrode on either
the first surface 104 or the second surface 106 of semiconductor
chip 102 is electrically coupled to a third flexible lead 116
through a third solder or sintered joint. Mold compound 118
encapsulates semiconductor chip 102 and portions of flexible leads
112, 114, and 116.
[0025] Flexible leads 112, 114, and 116 enable semiconductor device
100 to be mounted onto a conventional flat Printed Circuit Board
(PCB) or onto a flexible PCB. In one embodiment, flexible leads
112, 114, and 116 are ribbon leads in which a width 126, 122, and
124 of each lead is greater than a thickness 120 of each lead. In
one embodiment, thickness 120 of flexible leads 112, 114, and 116
is between about 0.05 mm and 0.1 mm, width 122 of flexible lead 114
is greater than 2 mm, width 124 of flexible lead 116 is between
about 0.7 mm and 1 mm, and width 126 of flexible lead 112 is
greater than 2 mm. In other embodiments, the width of each flexible
lead is at least ten times greater than the thickness of each
flexible lead. In one embodiment, width 126 of flexible lead 112 is
greater than width 124 of flexible lead 116, and width 122 of
flexible lead 114 is greater than width 126 of flexible lead
112.
[0026] Flexible leads 112, 114, and 116 may include copper, lead
free alloys, or other suitable materials. In one embodiment,
flexible leads 112, 114, and 116 are made of pre-formed copper or
another suitable electrically conductive material such that
flexible leads 112, 114, and 116 have a spring-like characteristic
in which the leads return to their original shape after being
pressed, twisted, or stretched. In other embodiments, flexible
leads 112, 114, and 116 are made of an elastic or softening
material, such as a solder material, that enables the leads to be
flexible. For example, flexible lead 112, 114, and 116 may be made
of Au--Si, Au--Ge, Au--Sn, Pb--In, Sn--Cu, Sn--Cu--Ni, Sn--Ag,
Sn--Ag--Cu, Sn--Ag--Cu--Sb, Sn--Pb, or Bi--Sn.
[0027] Semiconductor chip 102 includes a Metal-Oxide-Semiconductor
Field-Effect Transistor (MOSFET) or an Insulated Gate Bipolar
Transistor (IGBT). In other embodiments, semiconductor chip 102
includes a diode or another suitable component. In one embodiment,
first flexible lead 112 is electrically coupled to a source
electrode, second flexible lead 114 is electrically coupled to a
drain electrode, and third flexible lead 116 is electrically
coupled to a gate electrode of a MOSFET semiconductor chip 102. In
another embodiment, first flexible lead 112 is electrically coupled
to an emitter electrode, second flexible lead 114 is electrically
coupled to a collector electrode, and third flexible lead 116 is
electrically coupled to a base electrode of an IGBT semiconductor
chip 102. Flexible leads 112, 114, and 116 are suitable for high
current applications in which the flexible leads may experience
high temperatures (e.g., up to 200.degree. C.) due to the high
currents.
[0028] In one embodiment, each flexible lead 112, 114, and 116 is
electrically coupled to semiconductor chip 102 by soft soldering
with Sn--Pb, Sn--Ag, Sn--Ag--Cu, or another suitable solder alloy.
In another embodiment, each flexible lead 112, 114, and 116 is
electrically coupled to semiconductor chip 102 by diffusion
soldering with Cu--Sn, Cu--Sn, Sn--Ag, Sn--Ni, or another suitable
alloy to provide an intermetallic joint between each flexible lead
112, 114, and 116 and semiconductor chip 102. Each flexible lead
112, 114, and 116 may also be electrically coupled to semiconductor
chip 102 by sintering with Au, Ag, Cu, or another suitable
metal.
[0029] Mold compound 118 includes a hard mold compound or a soft
mold compound. For example, the hard mold compound may include
epoxy, cross-linked or cross-linkable polymer, plastic, resin, or
other electrically insulating material. The soft mold compound may
include an elastic or flexible electrically insulating material,
such as any gel or elastic like material (e.g., rubber, silicone,
gel, or polymer such as Hydro-Carbon, CxHy). In one embodiment, a
heat sink is attached to mold compound 118 of semiconductor device
100 to dissipate heat generated by semiconductor chip 102.
[0030] FIG. 2 illustrates a side view of one embodiment of a
semiconductor device 128. Semiconductor device 128 includes a mold
compound 130 encapsulating a semiconductor chip and pre-formed
flexible leads 132 and 134 electrically coupled to the
semiconductor chip. In this embodiment, flexible leads 132 and 134
are not flexed and mold compound 130 is not flexed. Accordingly,
mold compound 130 may include a hard mold compound in this
embodiment.
[0031] FIG. 3 illustrates a side view of another embodiment of
semiconductor device 128. In this embodiment, flexible lead 132 is
flexed downward as indicated at 136, and flexible lead 134 is
flexed upward as indicated at 138. Flexible leads 132 and 134 are
flexed without damaging the leads. Mold compound 130 is not flexed
in this embodiment. Accordingly, mold compound 130 may include a
hard mold compound in this embodiment.
[0032] FIG. 4 illustrates a side view of another embodiment of
semiconductor device 128. In this embodiment, mold compound 130 is
flexed upward as indicated at 140. Mold compound 130 is flexed
without damaging the mold compound, the semiconductor chip
encapsulated by the mold compound, or flexible leads 132 and 134.
Mold compound 130 includes a soft mold compound in this
embodiment.
[0033] FIG. 5A illustrates a side view of one embodiment of a
flexible lead 150. Flexible lead 150 is flat and comprises an
elastic or softening material. In one embodiment, flexible lead 150
is used in place of flexible leads 112, 114, and 116 previously
described and illustrated with reference to FIGS. 1A and 1B.
[0034] FIG. 5B illustrates a side view of another embodiment of a
flexible lead 152. Flexible lead 152 includes end portions 154a and
154b and a central portion 156. End portion 154a is flat and is
connected to one side of central portion 156, and end portion 154b
is flat and is connected to the other side of central portion 156.
Central portion 156 is M-shaped and includes a plurality of flat
segments connected to each other at points as indicated for example
at 158. In this embodiment, central portion 156 includes four
segments connected to each other. In other embodiments, however,
central portion 156 may include any suitable number of segments
connected to each other in a zigzag manner. In one embodiment,
flexible lead 152 is used in place of flexible leads 112, 114, and
116 previously described and illustrated with reference to FIGS 1A
and 1B.
[0035] FIG. 5C illustrates a side view of another embodiment of a
flexible lead 162. Flexible lead 162 includes end portions 164a and
164b and a central portion 166. End portion 164a is flat and is
connected to one side of central portion 166, and end portion 164b
is flat and is connected to the other side of central portion 166.
Central portion 166 is serpentine-shaped and includes a plurality
of segments connected to each other at curved regions as indicated
for example at 168. In this embodiment, central portion 166
includes six segments connected to each other. In other
embodiments, however, central portion 166 may include any suitable
number of segments connected to each other in a serpentine manner.
In one embodiment, flexible lead 162 is used in place of flexible
leads 112, 114, and 116 previously described and illustrated with
reference to FIGS. 1A and 1B.
[0036] While FIGS. 5A-5C illustrate three embodiments of flexible
leads having different shapes, the flexible leads may have any
suitable shape that enables the leads to be flexible.
[0037] FIG. 6A illustrates a side view of one embodiment of a
semiconductor device 200a coupled to a Printed Circuit Board (PCB)
202. Semiconductor device 200a is surface mounted onto a flat PCB
202. Semiconductor device 200a includes a mold material 204
encapsulating a semiconductor chip and portions of flexible leads
206a, 208a, and 210a. Flexible leads 206a, 208a, and 210a are flat
and comprise an elastic or softening material. In one embodiment,
flexible lead 206a is electrically coupled to a drain electrode,
flexible lead 208a is electrically coupled to a source electrode,
and flexible lead 210a is electrically coupled to a gate electrode
of a MOSFET semiconductor chip encapsulated by mold compound 204.
In another embodiment, flexible lead 206a is electrically coupled
to a collector electrode, flexible lead 208a is electrically
coupled to an emitter electrode, and flexible lead 210a is
electrically coupled to a base electrode of an IGBT semiconductor
chip encapsulated by mold compound 204.
[0038] FIG. 6B illustrates a side view of one embodiment of a
semiconductor device 200b coupled to a PCB 202. Semiconductor
device 200b is similar to semiconductor device 200a previously
described and illustrated with reference to FIG. 6A, except that
semiconductor device 200b includes flexible leads 206b, 208b, and
210b. Flexible leads 206b, 208b, and 210b are pre-formed and
include a curved portion that in one embodiment gives flexible
leads 206b, 208b, and 210b a spring-like characteristic. In other
embodiments, flexible leads 206b, 208b, and 210b comprise an
elastic or softening material.
[0039] FIG. 7A illustrates a side view of one embodiment of
semiconductor device 200a coupled to a flexible PCB 220. Flexible
PCB 220 is curved and flexible leads 206a, 208a, and 210a and mold
compound 204 flex to match the curvature of flexible PCB 220.
Flexible leads 206a, 208a, and 210a and mold compound 204 flex
without damaging flexible leads 206a, 208a, and 210a or mold
compound 204.
[0040] FIG. 7B illustrates a side view of one embodiment of
semiconductor device 200b coupled to a flexible PCB 220. In this
embodiment, flexible leads 206b, 208b, and 210b and mold compound
204 flex to match the curvature of flexible PCB 220. Flexible leads
206b, 208b, and 210b and mold compound 204 flex without damaging
flexible leads 206b, 208b, and 210b or mold compound 204.
[0041] FIGS. 8A-8E illustrate one embodiment of a method for
fabricating a semiconductor device. FIG. 8A illustrates a top view
of one embodiment of a flexible ribbon lead 300 including a first
portion 302, a second portion 304, and a third portion 306. First
portion 302 is for electrically coupling lead 300 to a
semiconductor chip. Second portion 304 is U-shaped and extends
between the first portion 302 and the third portion 306. In one
embodiment, second portion 304 gives flexible lead 300 a
spring-like characteristic. Third portion 306 is for electrically
coupling lead 300 to a PCB.
[0042] FIG. 8B illustrates a top view of one embodiment of a
semiconductor chip 310 electrically coupled to flexible lead 300.
Semiconductor chip 310 includes a first electrode 312 (indicated by
dashed lines) on a bottom side of the semiconductor chip, and a
second electrode 314 and a third electrode 316 on a top side of the
semiconductor chip. In one embodiment, semiconductor chip 310 is a
MOSFET semiconductor chip, and first electrode 312 is a drain
electrode, second electrode 314 is a source electrode, and third
electrode 316 is a gate electrode. In another embodiment,
semiconductor chip 310 is an IGBT semiconductor chip, and first
electrode 312 is a collector electrode, second electrode 314 is an
emitter electrode, and third electrode 316 is a base electrode.
First electrode 312 of semiconductor chip 310 is connected to first
portion 302 of flexible lead 300 by soft soldering, diffusion
soldering, sintering, or other suitable method to electrically
couple first electrode 312 to flexible lead 300. In one embodiment,
semiconductor chip 310 is connected to flexible lead 300 such that
part of first portion 302 of flexible lead 300 extends past an edge
315 of semiconductor chip 310 by a distance indicated at 303.
[0043] FIG. 8C illustrates a top view of one embodiment of
semiconductor chip 310 electrically coupled to flexible lead 300
and a flexible lead 320. Flexible lead 320 is a flexible ribbon
lead including a first portion 322, a second portion 324, and a
third portion 326. First portion 322 is for electrically coupling
lead 300 to a semiconductor chip. Second portion 324 is U-shaped
and extends between the first portion 322 and the third portion
326. In one embodiment, second portion 324 gives flexible lead 320
a spring-like characteristic. Third portion 326 is for electrically
coupling lead 320 to a PCB. Second electrode 314 of semiconductor
chip 310 is connected to first portion 322 of flexible lead 320 by
soft soldering, diffusion soldering, sintering, or other suitable
method to electrically couple second electrode 314 to flexible lead
320.
[0044] FIG. 8D illustrates a top view of one embodiment of
semiconductor chip 310 electrically coupled to flexible lead 300,
flexible lead 320, and a flexible lead 330. Flexible lead 330 is a
flexible ribbon lead including a first portion 332, a second
portion 334, and a third portion 336. First portion 332 is for
electrically coupling lead 330 to a semiconductor chip. Second
portion 334 is U-shaped and extends between the first portion 332
and the third portion 336. In one embodiment, second portion 334
gives flexible lead 330 a spring-like characteristic. Third portion
336 is for electrically coupling lead 330 to a PCB. Third electrode
316 of semiconductor chip 310 is connected to first portion 332 of
flexible lead 330 by soft soldering, diffusion soldering,
sintering, or other suitable method to electrically couple third
electrode 316 to flexible lead 330.
[0045] FIG. 8E is a top view illustrating one embodiment of a mold
compound 340 encapsulating semiconductor chip 310 and portions of
flexible leads 300, 320, and 330. A hard or soft mold compound 340
is applied to semiconductor chip 310 and first portions 302, 322,
and 332 of flexible leads 300, 320, and 330, respectively, by an
injection molding process or another suitable process. The
semiconductor device may then be surface mounted onto a flat PCB as
previously described and illustrated with reference to FIGS. 6A and
6B or surface mounted onto a flexible PCB that may be flexed such
that the PCB is curved as previously described and illustrated with
reference to FIGS. 7A and 7B.
[0046] FIG. 9A illustrates a cross-sectional view, FIG. 9B
illustrates a top view, and FIG. 9C illustrates a bottom view of
one embodiment of a mold compound arrangement for a semiconductor
device 400. Semiconductor device 400 includes a semiconductor chip
102, flexible leads 300, 320, and 330, and a mold compound 402. In
this embodiment, mold compound 402 encapsulates semiconductor chip
102, first portion 302 of flexible lead 300, first portion 322 of
flexible lead 320, and first portion 332 (FIG. 8D) of flexible lead
330.
[0047] FIG. 10A illustrates a cross-sectional view, FIG. 10B
illustrates a top view, and FIG. 10C illustrates a bottom view of
one embodiment of a mold compound arrangement for a semiconductor
device 410. Semiconductor device 410 includes a semiconductor chip
102, flexible leads 300, 320, and 330, and a mold compound 412. In
this embodiment, mold compound 412 encapsulates semiconductor chip
102, first portion 302 of flexible lead 300, and first portion 332
(FIG. 8D) of flexible lead 330. First portion 322 of flexible lead
320 remains exposed.
[0048] FIG. 11A illustrates a cross-sectional view, FIG. 11B
illustrates a top view, and FIG. 11 C illustrates a bottom view of
one embodiment of a mold compound arrangement for a semiconductor
device 420. Semiconductor device 420 includes a semiconductor chip
102, flexible leads 300, 320, and 330, and a mold compound 422. In
this embodiment, mold compound 422 encapsulates semiconductor chip
102, first portion 302 of flexible lead 300, and first portion 332
(FIG. 8D) of flexible lead 330. First portion 322 of flexible lead
320 remains exposed except for a spacer portion 424 of mold
compound 422. In one embodiment, when mounted on a PCB, spacer
portion 424 defines an air gap or an area for placing a micro heat
sink or micro pipes between the PCB and first portion 322 of
flexible lead 320.
[0049] FIG. 12A illustrates a cross-sectional view, FIG. 12B
illustrates a top view, and FIG. 12C illustrates a bottom view of
one embodiment of a mold compound arrangement for a semiconductor
device 430. Semiconductor device 430 includes a semiconductor chip
102, flexible leads 300, 320, and 330, and a mold compound 432. In
this embodiment, mold compound 432 encapsulates semiconductor chip
102. First portion 302 of flexible lead 300, first portion 332 of
flexible lead 330, and first portion 322 of flexible lead 320
remain exposed.
[0050] FIG. 13A illustrates a cross-sectional view, FIG. 13B
illustrates a top view, and FIG. 13C illustrates a bottom view of
one embodiment of a mold compound arrangement for a semiconductor
device 440. Semiconductor device 440 includes a semiconductor chip
102, flexible leads 300, 320, and 330, and a mold compound 442. In
this embodiment, mold compound 442 encapsulates semiconductor chip
102. First portion 302 of flexible lead 300 remains exposed except
for a spacer portion 444 of mold compound 442. First portion 332 of
flexible lead 330 also remains exposed except for spacer portion
444 of mold compound 442. First portion 322 of flexible lead 320
remains exposed except for a spacer portion 446 of mold compound
442. In one embodiment, when mounted on a PCB, spacer portion 446
defines an air gap or an area for placing a micro heat sink or
micro pipes between the PCB and first portion 322 of flexible lead
320.
[0051] FIG. 14A illustrates one embodiment of a flexible lead
arrangement for a semiconductor device 500a. Semiconductor device
500a includes flexible leads 300, 320, and 330 and a mold compound
502a encapsulating a semiconductor chip. In one embodiment, the
semiconductor chip encapsulated by mold compound 502a is a MOSFET
semiconductor chip, and flexible lead 300 is electrically coupled
to a drain electrode, flexible lead 320 is electrically coupled to
a source electrode, and flexible lead 330 is electrically coupled
to a gate electrode of the semiconductor chip. In another
embodiment, the semiconductor chip encapsulated by mold compound
502a is an IGBT semiconductor chip, and flexible lead 300 is
electrically coupled to a collector electrode, flexible lead 320 is
electrically coupled to an emitter electrode, and flexible lead 330
is electrically coupled to a base electrode of the semiconductor
chip.
[0052] In this embodiment, flexible lead 300 extends from a first
side 504 of the semiconductor chip, flexible lead 320 extends from
a second side 506 of the semiconductor chip, and flexible lead 330
extends from a third side 508 of the semiconductor chip. First side
504 is opposite to second side 506, and third side 508 extends
between first side 504 and second side 506.
[0053] FIG. 14B illustrates one embodiment of a flexible lead
arrangement for a semiconductor device 500b. Semiconductor device
500b includes flexible leads 300, 320, and 330 and a mold compound
502b encapsulating a semiconductor chip. In this embodiment,
flexible lead 330 extends from first side 504 of the semiconductor
chip, and flexible leads 300 and 320 extend from second side 506 of
the semiconductor chip.
[0054] FIG. 14C illustrates one embodiment of a flexible lead
arrangement for a semiconductor device 500c. Semiconductor device
500c includes flexible leads 300, 320, and 330 and a mold compound
502c encapsulating a semiconductor chip. In this embodiment,
flexible leads 300 and 330 extend from first side 504 of the
semiconductor chip, and flexible lead 320 extends from second side
506 of the semiconductor chip.
[0055] FIG. 14D illustrates one embodiment of a flexible lead
arrangement for a semiconductor device 500d. Semiconductor device
500d includes flexible leads 300, 320, and 330 and a mold compound
502d encapsulating a semiconductor chip. In this embodiment,
flexible leads 300, 320, and 330 extend from the same side 506 of
the semiconductor chip. Flexible lead 320 is arranged between
flexible lead 330 and flexible lead 300.
[0056] While FIGS. 14A-14D illustrate several embodiments for the
arrangement of the flexible leads of a semiconductor device, in
other embodiments the flexible leads may have other suitable
arrangements.
[0057] FIG. 15 illustrates a side view of one embodiment of a
semiconductor device 600 including ferrite coils around the
flexible leads. Semiconductor device 600 includes flexible leads
604 and 606 and a mold material 602 encapsulating a semiconductor
chip. A first ferrite coil 608 is arranged around flexible lead
604, and a second ferrite coil 610 is arranged around flexible lead
606. The diameter of the ferrite coils 608 and 610 may be between
about 1 mm and 24 mm. In one embodiment, ferrite coils 608 and 610
reduce noise on signals transmitted through flexible leads 604 and
606, respectively.
[0058] FIG. 16A illustrates one embodiment of a flexible lead
arrangement for a semiconductor device 700a including an
additional, or fourth flexible lead. In one example, the additional
flexible lead is a source sense flexible lead 708. Semiconductor
device 700a includes flexible leads 300, 320, 330, and 708 and a
mold compound 702a encapsulating a semiconductor chip. In one
embodiment, the semiconductor chip encapsulated by mold compound
702a is a MOSFET semiconductor chip, and flexible lead 320 is
electrically coupled to a drain electrode, flexible lead 300 is
electrically coupled to a source electrode, flexible lead 330 is
electrically coupled to a gate electrode, and flexible lead 708 is
electrically coupled to a source sense electrode of the
semiconductor chip.
[0059] In this embodiment, flexible leads 300, 330, and 708 extend
from a first side 704 of the semiconductor chip, and flexible lead
320 extends from a second side 706 of the semiconductor chip. First
side 704 of the semiconductor chip is opposite to second side
706.
[0060] FIG. 16B illustrates another embodiment of a flexible lead
arrangement for a semiconductor device 700b including a source
sense flexible lead 708. Semiconductor device 700b includes
flexible leads 300, 320, 330, and 708 and a mold compound 702b
encapsulating a semiconductor chip. In this embodiment, flexible
leads 330 and 708 extend from first side 704 of the semiconductor
chip, and flexible leads 300 and 320 extend from second side 706 of
the semiconductor chip.
[0061] While FIGS. 16A-16B illustrate two embodiments for the
arrangement of the flexible leads of a semiconductor device, in
other embodiments the flexible leads may have other suitable
arrangements.
[0062] Embodiments of the disclosure provide semiconductor devices
including flexible leads. The flexible leads enable the
semiconductor devices to be mounted on flexible PCBs that may be
curved without damaging the semiconductor devices. Further
embodiments of the disclosure provide semiconductor devices
including a flexible mold compound in addition to the flexible
leads. The flexible leads and/or the flexible mold compound enable
the semiconductor devices to be used in a wide variety of
applications, such as portable electronic devices (e.g., mobile
phones) having different shapes and sizes.
[0063] Although specific embodiments have been illustrated and
described herein, it will be appreciated by those of ordinary skill
in the art that a variety of alternate and/or equivalent
implementations may be substituted for the specific embodiments
shown and described without departing from the scope of the present
disclosure. This application is intended to cover any adaptations
or variations of the specific embodiments discussed herein.
Therefore, it is intended that this disclosure be limited only by
the claims and the equivalents thereof.
* * * * *